Dual Party Relay (DPR) service is a service that allows a sound-impaired (i.e., hearing or speech impaired) individual to communicate, via a telephone connection, with an individual who is not so impaired. An impaired individual may do this by dialing a particular telephone number(s) to establish a connection to a so-called DPR attendant who is trained to "translate" and relay the ensuing conversation.
In particular, a hearing-impaired person may place a telephone call to a DPR center via a device commonly referred to as a Telecommunications Device for the Deaf (TDD). A TDD has an alphanumeric keyboard and either a full screen or a single line character display, and employs either BAUDOT or ASCII signaling or both. The hearing-impaired person (hereinafter also referred to as TDD user) operating the TDD keyboard enters a text message, which is transmitted via a telephone connection and displayed at an attendant console. An attendant positioned at the console transmits via a separate telephone connection to the unimpaired person an oral version of the displayed text message. The attendant then listens to and enters via a console keyboard for transmission via the telephone connection to the TDD for display thereat a text message corresponding to the unimpaired person's oral response. The attendant continues such translation services for the duration of the DPR telephone call.
More specifically, if the TDD user can speak but cannot hear, then a switching state referred to as "Voice CarryOver" (VCO) allows that TDD user to speak directly to the unimpaired person. If, on the other hand, the TDD user can hear but cannot speak then a switching state referred to as "Hearing CarryOver" (HCO) allows that TDD user to receive speech directly from the unimpaired person. In the first instance, the attendant translates the unimpaired person's verbal response into text for the benefit of the hearing impaired TDD user, and in the second instance, the attendant translates the TDD user's text message into speech for benefit of the unimpaired person.
It can be appreciated from the foregoing that the cost of a DPR telephone call is not insignificant, since the aforementioned translation service is labor intensive.
It has been suggested that a Text-To-Speech (TTS) synthesizer and possibly automatic speech recognition could be employed to perform such translation services, thereby decreasing the amount of time an attendant is involved in serving DPR calls, and thereby decreasing the cost of such calls. The way in which a TTS synthesizer and/or automatic speech recognition could be employed in a dual party relay system is not obvious, and the implementation of either one of those features is not a trival task.
Currently, large interexchange carriers offer a number of so-called enhanced services, such as, for example, electronic mail services, which store a voice and/or textual message and then, at a later time, forward the message to an identified recipient. However, sound impaired persons cannot take advantage of such enhanced services. The reason for this is that such services typically require a caller to respond to prerecorded verbal instructions to invoke the respective service.